| 1. Attachment of muscles through tendons
2. Protection of vital organs such as nervous system in cranial cavity
3. Reservoirs of minerals such as calcium and phosphorous
4. Hemopoiesis: manufacture of blood cells in red bone narrow
5. Storage of triglycerides (fat storage) stored in yellow marrow | Discuss the 5 functions of support, protection, assistance in movement, mineral homeostasis, blood cell production, and triglyceride storage. |
| Longer than they are wide
EX: humerus, femur, phalanges, etc. | Long Bones |
| Cube shaped
EX: wrist and ankle bone | Short Bones |
| thin, flattened, and a bit curved
EX: Sternum, scapula, ribs, and skull | Flat Bones |
| Vertebrae and hip bones | Irregular bones |
| special type of short bone that develop in tendons under stress
Patella | Sesamoid Bones |
| shaft hollow in middle of bone and contains mostly yellow marrow | Diaphysis in Long Bone and what type of marrow? |
| Runs length of diaphysis and contains yellow marrow (storage of triglycerides) | Medullary cavity in long bone and what type of marrow? |
| ends of bone
Red marrow in proximal epiphysis of femur and humerus
Yellow marrow in distal end of epiphysis | Epiphysis in Long bone and what type of marrow? |
| Between diaphysis and epiphysis | Metaphysis in long bone |
| A layer of hyaline cartilage that allows diaphysis to grow in length
-Growth plate | Epiphyseal plate in long bone |
| Bony structure that replaces epiphyseal plate when bone stops growing | Epiphyseal line in Long Bone |
| Outside covering of bone except at joint surface and present as 2 layers | Periosteum |
| Osteoprogenitor cells and osteoblasts | Inner layer of Periosteum contains what cells? |
| Dense irregular CT (fibrous layer) | Outter layer of periosteum is made of what CT? |
| Outer layer because it contains blood vessels, lymph vessels, nerves that pass into bone | Is the inner or outer layer of periosteum vascular? |
| osteoprogenitor cells, osteoblasts, and osteoclasts | Endosteum of long bone consists of what cells? |
| line medullary cavity, central and volksmann canals, and covers trabeculae of spongy bone | Endosteum of long bone lines what cavities? |
| Covers each epiphysis
Hyaline cartilage | Articular cartilage of long bone covers what surface and is made of what cartilage? |
| friction and damage at joints | What does articular cartilage prevent? |
| Derived from menenchyme (CT)
Capable of mitosis and develops into osteoblasts
Located in inner periosteum and endosteum in volksmann and central canals | Osteoprogenitor Cells: what CT, capable of mitosis? Location? |
| Derived from menenchyme (CT)
Capable of mitosis and develops into osteoblasts
Located in inner periosteum and endosteum in volksmann and central canals | Osteoprogenitor Cells: what CT, capable of mitosis? Location? |
| -NOT capable of mitosis
-Produce collagen and bone tissue
-Located in inner periosteum and endosteum in volksmann and central canals
-Secrete bone matrix | Osteoblasts: capable of mitosis? What fiber and tissue is produced? Location? Secrete what? |
| -Moniter and mineralize bone matrix
-Located in lacuna
-Mature bone cell | Osteocytes: Location? What is it? Function? |
| -Develop from monocytes
Release collagenase and acids
-Located in endosteum | Osteoclasts: develop from? Releases what that digests bone? Location? |
| Osteoprogenitor, osteoblasts, osteocytes, bone lining cells, and osteoclasts | Soft Organic Components: which cells allow bone to resist tension (stretch) |
| Sacrificial Bonds: stretch and break easily on impact, helping prevent fractures | Soft organic components: what type of bonds? |
| Mineral salts: calcium phosphate located around collagen fibers | Hard Inorganic Components? |
| a. 25% water, 25% collagen fiber, 50% calcium phosphate
b. collagen fibers produced by osteoblasts
c. Osteoblasts become trapped in lacuna; known as osteocytes
d. Cytoplasmic extensions from osteocytes are located in canalculi
e. Matrix arranged in concentric rings around central canal called lamella
f. Osteon: central canal and surrounding lamella | Process of creating an osteon |
| 1. Made of TRABECULAE
2. Fill inner layer of most bones
3. Bone marrow cavity absent
4. Bone marrow produces red corpuscles and white granular corpuscles
5. Forms the ends of epiphyses of long bones | 5 Characteristics of Spongy Bone |
| 1. Made of OSTEONS
2. Fill outer layer of most bones
3.Bone marrow cavity present in center
4. Bone marrow stores fat
5. Forms shaft or diaphysis of long bone | 5 Characteristics of Compact bone |
| Centrally located mesenchymal cells cluster and differentiate into osteoblasts forming an ossification center that produces the first trabeculae of spongy bone | Step 1 of Intramembranous Formation |
| -Osteoblasts begin to secrete osteoid, which calcifies in a few days
-Trapped osteoblasts become osteocytes | Step 2 of Intramembranous Ossification |
| -Accumulating osteoid is laid down between embryonic blood vessels in a manner that results in a network of trabeculae
-Vascularized mesenchyme condenses on the external face of the woven bone and becomes the periosteum | Step 3 of Intramembranous Ossification |
| -Trabeculae just deep to the periosteum thickens and mature lamellar bone replaces them forming compact bone plates
-Spongy bone consisting of distinct trabeculae persists internally and its vascular tissue becomes red marrow | Step 4 of Intramembranous Ossification |
| 1. Blood vessels penetrate the perichondrium in center of diaphysis and stimulate osteoprogenitor cells of internal layer of perichondrium to enlarge and become osteoblasts
2. Osteoblasts secrete enzyme, encouraging Ca salts to secrete matrix
3. Osteoblasts form thin layer of calcified bone (bony collar)
4. Bony collar and newly calcified matrix restrict nutrient flow to chondrocytes, so they die opening cavities
5. In cavities, osteoblasts form new spongy bone tissue
6. Osteoclasts digest out more cavity, forming marrow cavity for diaphysis | Enchondrial Ossification: Steps at primary ossification center |
| -More blood vessels enter diaphysis bringing with osteoprogenitor cells that develop into osteoblasts which produce spongy bone
-Secondary centers do not begin until after birth
-After secondary centers have formed, bone tissue completely replaces cartilage except in Articular cartilage and epiphyseal plate | Enchondrial Ossification: Steps of Secondary Ossification Center |
| Resting Zone: epiphyseal side (no mitosis)
Proliferating cartilage zone: mitosis
Hypertrophic cartilage zone: cartilage cells enlarging, older chondrocytes in stack are closer to diaphysis, lacunae erode and enlarge, leaving interconnecting spaces
Calcified cartilage zone: dying cartilage cells on diaphyseal plate , matrix begins to deteriorate, allowing blood vessels to invade
Ossification Zone: calcified spicules are invaded marrow elements from mudullary cavity, osteoclasts partly erode cartilage spicules then osteoblasts cover them with new bone | 4 Zones of epiphyseal plate |
| 1. New osteons are constructed on outside of bone
2. Osteoblasts from periosteum add new bone tissue, enclosing a blood vessel running through periosteum
3. Once blood vessel's enclosed, periosteum becomes endosteum inside the newly formed canal
4. Osteoblasts in endosteum continue to make more bone tissue in concentric rings resulting in a new osteon
5. While new bone is being made on outside of bone, osteoclasts in medullary cavity endosteum destroy bone lining marrow cavity | Growth in Thickness steps |
| Osteoclasts: move along bone surface, digging depressions as they break down bone matrix (break down to free calcium)
Osteoblasts: deposit calcium into bone, remaking it'
BOTH MAINTAIN CA HOMEOSTASIS AND KEEPS BONE STRONG | Discuss role of osteoclasts and osteoblasts in remodeling process |
| Normal bone growth in young people | Growth Hormone (pituitary gland and thyroxin) |
| Increases Ca in blood and increases blood calcium levels when they drop too low | Parathyroid Hormone |
| -Increases osteoblast activity
-Accelerates deposit of Ca into bone
-Blood Ca levels decrease
-Released from thyroid gland, decreases blood calcium levels when they are too high | Calcitonin (thyroid) |
| -Sun converts cholesterol into vitamin D
-Needed to absorb Ca from intestine | Vitamin D (calcitriol) |
| Decrease in vitamin D in children; cartilage cells grow; ossification occurs but little calcification; bones bow under weight because they are soft | Rickets |
| Decrease in vitamin D in adults | Osteomalacia |
| -Pourous bones
-Caused by decrease in sex hormones with increasing age; more popular in menapousing women | Osteoporosis (sex hormone) |
| Bacterial infection in bone (staph)
Bacteria reaches bone by blood, fractures, sinus infection, tooth abscess | Osteomyelitis |
| Malignant cancer of osteoblasts; predominant in young people
-spread is likely; amputation | Osteogenic Sarcoma |
| -Most common form of bone cancer
-Myeloid: marrow
-Can either start in bone or after metastasis from breast, prostate cancers, interferes with hemopoiesis (production of blood cells) | Malignant Myelomas |
| broken ends do not penetrate through skin | Simple/Closed fracture |
| broken ends protrude through skin | Compound/open fracture |
| bone shattered into many pieces | Comminuted fracture |
| Bone is crushed or driven into another bone | Compression/Impacted fracture |
| One side breaks, other side bends | Greenstick fracture |
| Broken bone portion is pressed inward | Depressed Fracture |
| ragged break occurs when excessive twisting forces are applied | Spiral Fracture |
| Epiphysis separates from diaphysis along epiphyseal plates | Epiphyseal Fracture |
| 1. Hematoma: from bleeding of blood vessel into osteons, periosteum, marrow cavity
2. Fibrocartilaginous callus: forms a bridge of fibrocartilage between separated area
3. Bony callus: growth of new bone tissue replaces fibrocartilage bone -remodels to be like other bone | Steps of Fracture Repair |
